Causes the current thread to wait until another thread invokes the
notify() method or the
notifyAll() method for this object, or
some other thread interrupts the current thread, or a certain
amount of real time has elapsed.

REPORTING_MODE_ON_CHANGE

Events are reported only when the value changes. Event delivery rate can be limited by
setting appropriate value for rate parameter of
SensorManager.registerListener(SensorEventListener, Sensor, int) Note: If other
applications are requesting a higher rate, the sensor data might be delivered at faster rates
than requested.

Constant Value:
1
(0x00000001)

REPORTING_MODE_SPECIAL_TRIGGER

Events are reported as described in the description of the sensor. The rate passed to
registerListener might not have an impact on the rate of event delivery. See the sensor
definition for more information on when and how frequently the events are reported. For
example, step detectors report events when a step is detected.

TYPE_GAME_ROTATION_VECTOR

Identical to TYPE_ROTATION_VECTOR except that it doesn't
use the geomagnetic field. Therefore the Y axis doesn't
point north, but instead to some other reference, that reference is
allowed to drift by the same order of magnitude as the gyroscope
drift around the Z axis.

In the ideal case, a phone rotated and returning to the same real-world
orientation should report the same game rotation vector
(without using the earth's geomagnetic field). However, the orientation
may drift somewhat over time.

TYPE_GEOMAGNETIC_ROTATION_VECTOR

Similar to TYPE_ROTATION_VECTOR, but using a magnetometer instead of using a
gyroscope. This sensor uses lower power than the other rotation vectors, because it doesn't
use the gyroscope. However, it is more noisy and will work best outdoors.

TYPE_GYROSCOPE_UNCALIBRATED

Similar to TYPE_GYROSCOPE but no gyro-drift compensation has been performed
to adjust the given sensor values. However, such gyro-drift bias values
are returned to you separately in the result SensorEvent.values
so you may use them for custom calibrations.

Factory calibration and temperature compensation is still applied
to the rate of rotation (angular speeds).

TYPE_HEART_RATE

The reported accuracy represents the status of the monitor during the reading. See the
SENSOR_STATUS_* constants in SensorManager
for more details on accuracy/status values. In particular, when the accuracy is
SENSOR_STATUS_UNRELIABLE or SENSOR_STATUS_NO_CONTACT, the heart rate
value should be discarded.

This sensor requires permission android.permission.BODY_SENSORS.
It will not be returned by SensorManager.getSensorsList nor
SensorManager.getDefaultSensor if the application doesn't have this permission.

TYPE_MAGNETIC_FIELD_UNCALIBRATED

Similar to TYPE_MAGNETIC_FIELD but the hard iron calibration (device calibration
due to distortions that arise from magnetized iron, steel or permanent magnets on the
device) is not considered in the given sensor values. However, such hard iron bias values
are returned to you separately in the result SensorEvent.values
so you may use them for custom calibrations.

Also, no periodic calibration is performed
(i.e. there are no discontinuities in the data stream while using this sensor) and
assumptions that the magnetic field is due to the Earth's poles is avoided, but
factory calibration and temperature compensation have been performed.

TYPE_POSE_6DOF

A constant describing a pose sensor with 6 degrees of freedom.
Similar to TYPE_ROTATION_VECTOR, with additional delta
translation from an arbitrary reference point.
See SensorEvent.values for more details.
Can use camera, depth sensor etc to compute output value.
This is expected to be a high power sensor and expected only to be
used when the screen is on.
Expected to be more accurate than the rotation vector alone.

TYPE_SIGNIFICANT_MOTION

It triggers when an event occurs and then automatically disables
itself. The sensor continues to operate while the device is asleep
and will automatically wake the device to notify when significant
motion is detected. The application does not need to hold any wake
locks for this sensor to trigger. This is a wake up sensor.

TYPE_STEP_COUNTER

A sensor of this type returns the number of steps taken by the user since the last reboot
while activated. The value is returned as a float (with the fractional part set to zero) and
is reset to zero only on a system reboot. The timestamp of the event is set to the time when
the last step for that event was taken. This sensor is implemented in hardware and is
expected to be low power. If you want to continuously track the number of steps over a long
period of time, do NOT unregister for this sensor, so that it keeps counting steps in the
background even when the AP is in suspend mode and report the aggregate count when the AP
is awake. Application needs to stay registered for this sensor because step counter does not
count steps if it is not activated. This sensor is ideal for fitness tracking applications.
It is defined as an REPORTING_MODE_ON_CHANGE sensor.

TYPE_STEP_DETECTOR

A sensor of this type triggers an event each time a step is taken by the user. The only
allowed value to return is 1.0 and an event is generated for each step. Like with any other
event, the timestamp indicates when the event (here the step) occurred, this corresponds to
when the foot hit the ground, generating a high variation in acceleration. This sensor is
only for detecting every individual step as soon as it is taken, for example to perform dead
reckoning. If you only need aggregate number of steps taken over a period of time, register
for TYPE_STEP_COUNTER instead. It is defined as a
REPORTING_MODE_SPECIAL_TRIGGER sensor.

Public methods

getFifoMaxEventCount

Maximum number of events of this sensor that could be batched. If this value is zero
it indicates that batch mode is not supported for this sensor. If other applications
registered to batched sensors, the actual number of events that can be batched might be
smaller because the hardware FiFo will be partially used to batch the other sensors.

getId

The sensor id that will be unique for the same app unless the device is factory
reset. Return value of 0 means this sensor does not support this function; return value of -1
means this sensor can be uniquely identified in system by combination of its type and name.

getMaxDelay

This value is defined only for continuous and on-change sensors. It is the delay between two
sensor events corresponding to the lowest frequency that this sensor supports. When lower
frequencies are requested through registerListener() the events will be generated at this
frequency instead. It can be used to estimate when the batch FIFO may be full. Older devices
may set this value to zero. Ignore this value in case it is negative or zero.

isWakeUpSensor

Application Processor(AP), is the processor on which applications run. When no wake lock is
held and the user is not interacting with the device, this processor can enter a “Suspend”
mode, reducing the power consumption by 10 times or more.

Non-wake-up sensors

Non-wake-up sensors are sensors that do not wake the AP out of suspend to report data. While
the AP is in suspend mode, the sensors continue to function and generate events, which are
put in a hardware FIFO. The events in the FIFO are delivered to the application when the AP
wakes up. If the FIFO was too small to store all events generated while the AP was in
suspend mode, the older events are lost: the oldest data is dropped to accommodate the newer
data. In the extreme case where the FIFO is non-existent maxFifoEventCount() == 0,
all events generated while the AP was in suspend mode are lost. Applications using
non-wake-up sensors should usually:

Either unregister from the sensors when they do not need them, usually in the activity’s
onPause method. This is the most common case.

Or realize that the sensors are consuming some power while the AP is in suspend mode and
that even then, some events might be lost.

Wake-up sensors

In opposition to non-wake-up sensors, wake-up sensors ensure that their data is delivered
independently of the state of the AP. While the AP is awake, the wake-up sensors behave
like non-wake-up-sensors. When the AP is asleep, wake-up sensors wake up the AP to deliver
events. That is, the AP will wake up and the sensor will deliver the events before the
maximum reporting latency is elapsed or the hardware FIFO gets full. See SensorManager.registerListener(SensorEventListener, Sensor, int, int) for more details.

Returns

boolean

true if this is a wake-up sensor, false otherwise.

toString

Returns a string representation of the object. In general, the
toString method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.

The toString method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of: